1. Technical Field
The present invention relates to microlens array substrates, electro-optic devices, and electronic apparatuses.
2. Related Art
A projector is an electronic apparatus that irradiates light to a transmissive electro-optic device, a reflective electro-optic device or the like, and projects the transmitted or reflected light having been modulated by the electro-optic devices onto a screen. The projector is configured so that light emitted from a light source is collected and made to enter the electro-optic device, and then the transmitted or reflected light that has been modulated in accordance with an electric signal is enlarged and projected onto a screen through a projection lens; the projector configured in this manner is advantageous in that it can magnify and display an image on a large screen. A liquid crystal device is widely known as an electro-optic device that is used in such electronic apparatus as described above; the liquid crystal device is configured to form an image by making use of dielectric anisotropy of liquid crystal and optical rotation of light in a liquid crystal layer.
Such liquid crystal device is required to be smaller in size and to increase the number of pixels in order to miniaturize an electronic apparatus and to enhance resolution of an image to be displayed. Meanwhile, in an electro-optic device, a region (aperture) where light is modulated is likely to become smaller (the aperture ratio decreases), as the electronic apparatus becomes smaller in size and the number of pixels is further increased. This has lowered efficiency in use of light supplied from a light source and made it difficult to display an image with high luminance. Therefore, in order to cover a decrease in the aperture ratio of a liquid crystal device, adopted is a method in which a microlens array is arranged on a light incidence side of the liquid crystal device to improve the efficiency in use of light. To be specific, minute microlenses are disposed corresponding to the apertures each of which being provided for each of pixels of the liquid crystal device.
As a microlens, an aspheric convex lens is well known as described in JP-A-2004-70282, for example. The liquid crystal device is configured by disposing a liquid crystal layer between a thin-film transistor (TFT) element substrate and an opposing substrate, and the microlenses are formed in the opposing substrate. More specifically, the aspheric convex microlenses are formed on a surface of the opposing substrate, a transparent plate member covers the microlenses, and the liquid crystal layer is disposed between the transparent plate member and the TFT element substrate.
However, in the electro-optic device described in JP-A-2004-70282, there is a problem in that the incident light on the microlens is not always efficiently introduced to the aperture for sure. That is, since the shape of the aspheric convex lens and the placement position of the microlens are not specified, the relationship between the shape of a beam of light outputted from the microlens and a light blocking portion that specifies the aperture is not optimized, which causes an issue that the efficiency in use of light is lowered.